Ophelia To Become Trough-elia?Added : Tuesday at 11:44 Half decent play on the name there we think... Worth a little nosy at Tropical Storm Ophelia for this discussion as the scenario played out by the ECMWF ► and GEM yesterday seems to be now be also on the cards for the GFS.
Bear in mind though that this is T+192 and we are also dealing with a tropical system, so DON'T take this as a forecast and more a skip along the flower filled meadow just glancing at what the numerical models are showing.
Right now, that is Tropical Storm Ophelia. The NHC are expecting her to increase to hurricane strength in the next day or so, but at the moment she is trapped in an upper level low which means that her movement is sort of restricted for the next day or two until an upper ridge builds in tomorrow.
By Friday and very little has changed, although Ophelia will continue to strengthen where she is thanks to a lack of shear and also an impressive temperature contrast between the warm Atlantic waters and colder than average upper air conditions.
Usually, hurricanes need that magic number of 27c at the surface in order to continue to feed and grow, but this is more down to the difference in temperature between the surface and the upper air. If the upper air is markedly cooler than average then the temperature contrast, or thermodynamic gradient allows deep convection to continue.
So, by early Saturday we have this :-
Then the change.... Ophelia is at the mercy of upper level winds. Into the weekend and the ridge weakens and an upper trough swings in from the Atlantic :-
It's how, why, if and when Ophelia interacts with this trough which decides what happens next week. The ECMWF ► goes for this :-
The GEM takes Ophelia further West with this :-
The GFS ► though interacts Ophelia with the incoming trough and brings us this :-
Still very much early days and it's possible all the global models are collapsing that ridge a little too quickly and Ophelia could end up either West of Ireland or affecting parts of Spain/Portugal, but an interesting meteorological scenario in the models at the moment and if you are interested in meteorology and the weather then worth following how the numerical models deal with this system over the next few days and not get too hung up on raw numerical output.
METEOROLOGIST : MARSH |